An intake unit for a baler is known as “open throat” where the opening from the pick up towards the inlet of the baler is open, and there are no devices present to forward the material towards the inlet of the baler, whereby the elements of these devices substantially “close” the surface of the inlet of the baler to ensure forwarding (and possibly cutting/processing) all of the material, i.e. an “undershot” rotor with tines.
In general, the purpose of a wide pickup baler is to collect crop material to be formed into a bale from a swath or windrow on the ground and to convey this material toward the inlet of the baler. Since swaths/windrows are typically wider than the inlet of the baler, and all material must be collected in a single pass, accordingly the pickup unit (that typically includes a series of radially extending rotating tines that extend into and “pick up” the crop material) is wider, e.g. 2 m, than the inlet of the baler, e.g. 1.2 m.
In such an arrangement the material collected at the outermost edges of the pickup unit must be directed/channelled transverse to the general direction of travel toward the inlet of the baler. If no provision is made for specifically directing crop material from the edges of the pickup toward the inlet then material will build up at the edges, ultimately leading to blockage of the material flow.
In an effort to address this problem U.S. Pat. No. 6,948,300 describes a pickup system where crop material is able to be transported sideways by the use of two pairs of augers positioned above the pickup and outside of the inlet. Crop material that is otherwise at the edge and outside the baler inlet is urged by the augers toward the inlet. However, this apparatus has the disadvantage that material must be transported over the pickup strippers which is not a smooth surface. Build up and blockage can occur as a result.
U.S. Pat. No. 5,848,523 describes the use of an additional “overshot” roller that extends all the way across the pickup, prior to the baler inlet. The outer ends of the roller include auger flightings in an appropriate pitch direction depending on rotation. Crop material is accordingly transported sideways over the auger toward the inlet, further urged by surface constructions on the inboard portion of the overshot roller. However, a disadvantage of this solution is that when a large volume of material is required to be processed, the auger does not have sufficient power to move the material quickly enough towards the inlet, causing blockages and a subsequent failure to pick up the full width of a swath or windrow.
U.S. Pat. No. 6,601,375 suggests an improvement over U.S. Pat. No. 5,848,523 by including a second pair of augers above the overshot roller auger sections. These augers (above and below) do not have retainer plates, but cooperate with each other to pinch the material and draw it forward into the direction of the inlet. However, while effective in low volume applications, if the material flow on the sides is high then a significant amount of material will be disposed on the outside edges of the baler inlet, resulting in an inconsistent density and size of the bale at the edges, compared to the centre. Furthermore, if yet larger volumes of material are required to be processed toward the inlet, together with already large volumes coming directly into the inlet from the pickup, then the total volume can cause a self-supporting blockage of crop material across the inlet. In effect, the required interaction of the augers limits the maximum volume.